package test;
import java.util.*;
public class Main2015033 {

	public static void main(String[] args) {
		Stack<Character> stack = new Stack<Character>();
        Scanner in = new Scanner(System.in);
        String str = in.next(); 
        for (int i = 0; i < str.length(); i++) {
            stack.push(str.charAt(i));
        }
    
        for (int j= 0; j < str.length();j++) {
            if (stack.pop() != str.charAt(j)) {
                System.out.println("no");
                break;
            }
            else {
                System.out.println("yes");
                break;
            }
        }
     }
}
